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This article addresses the fabrication of a novel and eco-friendly ceramic membrane based on basalt powder via press and sintering methods with a pore size of 1.5–2 μm. The basalt ceramic membrane (BCM) was grafted by SiO2 nanoparticles (50–60 nm) and ZnO nanorods (2.2 μm). The water permeability for the prepared membranes was measured 345.3, 701.4, and 801.9 L/m2 h bar for bare BCM, SiO2-BCM, and ZnO-BCM, respectively. The prepared membranes were used in Escherichia coli (E. coli) removal, and 100% E. coli removal efficiency was achieved at a transmembrane pressure of 0.5 bar for all membranes. The antimicrobial activities of the solid surfaces for BCM, SiO2-BCM, and ZnO-BCM were also studied using E. coli as a model test microorganisms. The antimicrobial activities for bare BCM, SiO2-BCM, and ZnO-BCM were 20.57%, 74.90%, and 100%, respectively. The results are of great importance in terms of the reusability of membranes and the prevention of biofilm formation in wastewater treatment processes.

A new impedimetric biosensing system based on kallikrein-related peptidase 4 (KLK 4) antigen-specific antibodies and a zinc(II) phthalocyanine tetracarboxylic acid (Zn-PcTCa) matrix material was developed for the first time in this study. First, a Zn-PcTCa-coated indium tin oxide surface was used as an interface matrix material for the immobilization of anti-KLK 4 antibodies, and they bound to the platform via amide bonds. In the presence of KLK 4 antigens, the anti-KLK 4 antibodies specifically captured these antigens and caused changes in the electrochemical properties of the system. Randles equivalent circuit was utilized to evaluate the impedimetric signal, which was measured with the help of an electrochemical impedance spectroscopy method. After the specific interaction, the electron transfer resistance (Rct) was remarkably increased and displayed a linear relationship with the level of the KLK 4 antigen in the range of 0.02-15 pg/mL, with a a detection limit of 6.8 fg/mL. The designed biosensor was able to detect a KLK 4 antigen with good sensitivity, excellent specificity, and high stability. In addition, because of having a low-cost and robust procedure for fabrication, it could be repeatedly used in several areas including clinical diagnosis.

Here, we report the development of a novel photoactive biomolecular nanoarchitecture based on the genetically engineered extremophilic photosystem I (PSI) biophotocatalyst interfaced with a single layer graphene via pyrene-nitrilotriacetic acid self-assembled monolayer (SAM). For the oriented and stable immobilization of the PSI biophotocatalyst, an His6-tag was genetically engineered at the N-terminus of the stromal PsaD subunit of PSI, allowing for the preferential binding of this photoactive complex with its reducing side towards the graphene monolayer. This approach yielded a novel robust and ordered nanoarchitecture designed to generate an efficient direct electron transfer pathway between graphene, the metal redox center in the organic SAM and the photo-oxidized PSI biocatalyst. The nanosystem yielded an overall current output of 16.5 µA·cm−2 for the nickel- and 17.3 µA·cm−2 for the cobalt-based nanoassemblies, and was stable for at least 1 h of continuous standard illumination. The novel green nanosystem described in this work carries the high potential for future applications due to its robustness, highly ordered and simple architecture characterized by the high biophotocatalyst loading as well as simplicity of manufacturing.

Ocakoglu, Kasim/0000-0003-2807-0425; Biyiklioglu, Zekeriya/0000-0001-5138-214X; Tuncel, Ayca/0000-0003-0699-3309 WOS: 000466823300017 Today, the problem of antimicrobial resistance is the most important cause of morbidity and mortality in the treatment of infectious diseases worldwide. Therefore, alternative treatment strategies are important for controlling infectious diseases. In the basic principle of antimicrobial photodynamic therapy (aPDT), when harmless light at the appropriate wavelength absorbed by the photosensitizer, undergoes a transition from a ground state to a triplet state. The triplet state photosensitizer can interact with enzym and substrate molecules to produce free radicals and radical ions, or with molecular oxygen resulting in the generation of singlet oxygen which leads to cell cytotoxicity of the microorganism. For this purpose, axially {4-[(1E)-3-oxo-3-(2-thienyl) prop-1-en-1-yl] phenoxy} group substituted silicon phthalocyanine (Es-SiPc) and subphthalocyanine (Es-SubPc) were synthesized by reaction of SiPcCl2, SubPcCl with (2E)-3-(4-hydroxyphenyl)-1-(2-thienyl)prop-2-en-1-one in the presence of NaH in toluene. The new Es-SiPc and Es-SubPc were characterized by standard spectroscopy methods. The effects of aPDT in the presence of phthalocyanines were investigated against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) strains. Also, singlet oxygen generation of Es-SiPc and Es-SubPc were investigated. Our results suggest that the aPDT in the presence of newly synthesized Es-SiPc and Es-SubPc has promising antibacterial effects on Gram-positive and Gram-negative bacteria.

Imidazolium bromide salts have been shown as potent antibiotic molecules that show structure-based bioactivity related to their cation alkyl side chain length. To enhance the bioavailability of lipophilic alkyl side chains herein, a 1,8-naphthalimide group containing imidazolium bromide salts bearing different lengths of alkyl chains (NIM1, 2, and 3) are coupled with fluorescent carbon dots (C-NIMs) through electrostatic and pi-pi interactions. Further, obtained nanocarriers were radio-labeled with iodine-131 (131I) to track the bacterial uptake of them by Staphylococcus aureus and Escherichia coli. Antibacterial activities were also investigated by the microdilution method. Comparison studies showed that both radiolabeling efficiency and lipophilicity increased when NIMs were integrated onto the CDots. More importantly, CDots resulted in 4-fold enhanced uptake of NIM1 by S. aureus bacterium as compared to pristine imidazolium bromide salts while at a higher number of alkyl chain lengths enhancement was 2-fold.

Photodynamic therapy (PDT) is a noninvasive therapy based on the photodynamic effect. in this study, we sought to determine intracellular uptake and in vivo photodynamic therapy potential of Zn phthalocyanine-loaded mesoporous silica nanoparticles (MSNPS) against pancreatic cancer cells. MSNPS were labeled with I-131; the radiolabeling efficiency was found to 95.5 +/- 1.2% in pH 9 and 60 min reaction time. Besides, the highest intracellular uptake yields of I-131-MSNPS nanoparticles in MIA PaCa-2, AsPC-1, and PANC-1 cells were determined as 43.9 +/- 3.8%, 41.8 +/- 0.2%, and 37.9 +/- 1.3%, respectively, at 24 h incubation time. in vivo PDT studies were performed with subcutaneous xenograft cancer model nude mice with AsPC-1 pancreatic cancer cells. For photodynamic therapy, 685 nm red laser light 100 J/cm(2) light dose using and 5-20 mu M ZnPc containing MSNPS concentrations were applied. Histopathological studies revealed that the ratio of necrosis in tumor tissue was higher in the treatment group than the control groups., Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [2214/A]; Ege University, Scientific Research Project (BAP)Ege University [16 NBE 001], This research was funded by the Scientific and Technological Research Council of Turkey (TUBITAK; grant number2214/A), Ege University, Scientific Research Project (BAP; grant Number: 16 NBE 001).

In this study, Subphthalocyanine (SubPc) and SubPc integrated TiO2 nanoparticles (SubPc- TiO2) were examined as theranostic agents. In vitro photodynamic therapy (PDT) efficiency of SubPc/SubPc-TiO2 and nuclear imaging potential of 131I labeled SubPc/TiO2-SubPc were determined on hepatocellular carcinoma (HepG2), colorectal adenocarcinoma (HT29) and human healthy lung (WI38) cell lines. As a result, 131I-SubPc and 131I-SubPc-TiO2 have been identified as a nuclear imaging agent for liver cancer. Additionally, 131I-SubPc-TiO2 has been found to be promising for imaging colon tumors. According to the in vitro photodynamic therapy studies, SubPc and SubPc-TiO2 were determined suitable PDT agents for liver and colon tumors. These results suggest that SubPc-TiO2 might be a theranostic agent with both PDT and nuclear imaging potential.

Ampicillin is a one of effective antibiotics against Gram-positive and Gram-negative bacteria. This study aimed to label ampicillin-loaded graphene oxide nanoflake (AMP-GO) with 99m Tc and evaluate of its in vitro binding to Staphylococcus aureus and Escherichia coli. Firstly, ampicillin was loaded into graphene oxide nanoflake prepared. AMP-GO was characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) techniques, and the amount of loaded ampicillin onto GO was determined by UV-Vis absorption spectroscopy. AMP and AMP-GO were labeled with 99m Tc using stannous chloride reducing agent. Labeling efficiency of 99m Tc-AMP-GO was found to be 97.66 ± 2.06%. 99m Tc-AMP-GO has higher binding efficiencies to both S. aureus and E. coli than 99m Tc-AMP. 99m Tc-AMP-GO could be promising candidate as agent infection nuclear imaging. Furthermore, in vivo studies of 99m Tc-AMP-GO with infected rats are planned to be performed.

Carbon dioxide assisted particle formation combined with electrospraying using supercritical CO2 (scCO2) as an aid (Carbon Dioxide Assisted Nebulization-Electrodeposition, CAN-ED) was used to produce Bortezomib loaded poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) P(3HB-co-3HHx) nanoparticles for sustained release. The morphology and structure of the prepared nanoparticles were investigated by SEM, TEM and FT-IR spectroscopy. Average diameter of particles obtained was 155nm and the average core sizes of P(3HB-co-3HHx) nanoparticles were between 6 and 13nm. The drug loading capacity, drug release and stability of Bortezomib loaded P(3HB-co-3HHx) nanoparticles were analyzed. The maximum loading capacity was achieved at pH=6.0 in phosphate buffer (K2HPO4/KH2PO4). It was found that temperature did not affect the stability of Bortezomib loaded nanoparticles and it was good both at 37°C and 4°C. This study pointed out that CAN-ED is a green method to produce P(3HB-co-3HHx) nanoparticles for pH responsive targeting of Bortezomib especially to parts of the body where size exclusion is not crucial.

In this work, reduced graphene oxide (rGO) based electrode materials were developed to achieve a hybrid supercapacitor (SC) function. Therefore, several synthesis methods were developed to prepare a cost effective and environmentally friendly rGO. Additionally, to maintain the high surface area, spinel lithium titanate (sLTO) nanoparticles (NPs) were synthesized and deposited on the rGO surface to inhibit the restacking of the rGO layers on graphite. Furthermore, the adequate Fe-doping of sLTO increased the ionic conductivity and the intercalation capacity, which is necessary for a SC performance. The sLTO/rGO-composites were electrochemically analysed by chronopotentiometry and electrochemical impedance spectroscopy (EIS) to determine the stability during charge/discharge cycling and the capacity, respectively. To overcome the drawback of LTO's low conductivity values, its value has been drastically increased by Fe-doping. The results demonstrated the remarkable cycling performance of the Fe:LTO/rGO composite as well as a higher capacity compared to LTO/rGO and pure rGO-electrodes. The thermal stability, degradation and weight loss of the sLTO/rGO in the temperature range between 20 °C and 800 °C were investigated by thermogravimetry (TG)/DTA. As a conclusion, it can be stated that, increasing the ionic conductivity by Fe-doping drastically increases the hybrid capacity of the SC electrodes.

In recent years, photocatalysis upon semiconductor-based hybrid materials has received much attention for the improved environmental effects and energy applications. Many good semiconductors such as ZnO have large bandgaps and suffer from fast charge recombination which hinders photocatalytic activity. One possible strategy to overcome this problem is introducing a narrow bandgap co-catalyst. Within the context of this study, triple hybrid nanostructures comprised of ZnO nanorods and MoS2/rGO (MG) co-catalyst were synthesized and characterized by various analytical methods. Accordingly, 25ZnO/75MG and 75ZnO/25MG hybrid materials were synthesized for two different MG co-catalyst comprised of 0.5% (named as 25ZnO/75MG1) and 5% (named as 25ZnO/75MG2) graphene oxide. The photocatalytic activities of the heterostructures and pristine ZnO nanorods were evaluated by the degradation of BR 18 dye, a common water pollutant mainly from the textile industry. When introduced with the co-catalyst, 25ZnO/75MG1 heterostructures achieved 100% degradation for 180 min. Furthermore, when the GO amount in the co-catalyst was increased to 5%, fully degradation of the dye solution was realized by 25ZnO/75MG2 in the first 30 min. These results are indicative of a positive synergistic effect of MoS2-rGO co-catalyst. Also, it is shown that increasing the GO amount is an effective approach to accelerate charge separation and electron transport properties.

This study aims to investigate the modification of polyethersulfone (PES) membrane with boron nitride quantum dots (BNQD) for improving the antifouling performance. The composite membranes were synthesized by blending different amounts of BNQD (0.50, 1.00, and 2.00 wt.%) into PES with the non-solvent induced phase separation (NIPS) method. UV–vis absorption, X-ray diffraction (XRD), and transmission electron microscopy (TEM) were used to characterize BNQD. Moreover, porosity, pore size, contact angle, permeability, bovine serum albumin (BSA) rejection, and antifouling properties were determined for composite membranes. The enhanced biological activity of BNQD was investigated based on antioxidant, antimicrobial, anti-biofilm, bacterial viability inhibition, and DNA cleavage studies. The BNQD showed 19.35 % DPPH radical scavenging activity and 76.45 % ferrous ion chelating activity at 500 mg/L. They also exhibited good chemical nuclease activity at all concentrations. BNQD had moderate antibacterial activity against all tested microorganisms. Biofilm inhibition percentage of BNQD was determined as 82.31 % at 500 mg/L. Cell viability assay demonstrated that the BNQD showed strong cell viability inhibition 99.9 % at the concentration of 1000 mg/L. The porosity increased from 56.83 ± 1.17%–61.83 ± 1.17 % while BNQD concentration increased from 0 to 2.00 wt%. Moreover, the hydrophilicity of BNQD nanocomposite membranes also increased from 75.42 ± 0.56° to 65.34 ± 0.25°. The mean pore radius is far slightly changed from 16.47 ± 0.35 nm to 19.16 ± 0.22 nm. The water flux increased from 133.5 ± 9.5 L/m2/h (for pristine membrane) to 388.6 ± 18.8 L/m2/h (for PES/BNQD 2.00 wt% membrane). BSA flux increased from 38.8 ± 0.9 L/m2/h to 63.2 ± 2.7 L/m2/h up to 1.00 wt% amount of BNQD nanoparticles.

This study aims to investigate the modification of polyethersulphone (PES) membrane with graphitic carbon nitride (g-C3N4) nanosheets for improving the antifouling and separation performance. The nanocomposite membranes were fabricated with blending of different g-C3N4 nanosheets (0.50, 1.00, and 2.00 wt%) into PES and they were synthesized by the phase inversion method. The fabricated g-C3N4 nanosheets and composite membranes were analyzed for their morphology. Scanning electron microscopy (SEM) with Energy Dispersive X-Ray Analysis (EDX) mapping were used to detect the distribution of g-C3N4 nanosheets on membrane surface, whereas surface roughness of membrane was evaluated by atomic force microscopy (AFM). The composite membrane surface was found to be hydrophilic (67.54°), while the water flux of the composite membrane was found to be 254.8 L/m2/h for 2.00 wt% g-C3N4/PES membrane. The bovine serum albumin (BSA) separation tests indicated that the composite membrane supplied 98.5% BSA rejection ratio. Moreover, a significant improvement in antifouling characteristics were verified from BSA filtration experiments. g-C3N4 was also investigated for some of its biological properties such as antioxidant, antimicrobial, DNA cleavage, biofilm inhibition, and bacterial viability effect. g-C3N4 showed good free radical scavenging activity and moderate chelating activity at 500 mg/L. It was also determined that single-strand DNA cleavage activities occurred at all tested concentrations. g-C3N4 exhibited significant antibiofilm activity and inhibitory effects on E. coli vitality as 90.9%, 97.1%, and 98.9% at 250, 500, and 1000 mg/L, respectively. This study provides a simple and useful guideline to create a UF membrane resistant against organic fouling and expand its practical applications for wastewater treatment.

The highly efficient bioelectrodes based on single layer graphene (SLG) functionalized with pyrene self-assembled monolayer and novel cytochrome c553 (cyt c553) peptide linker variants were rationally designed to optimize the direct electron transfer (DET) between SLG and the heme group of cyt. Through a combination of photoelectrochemical and quantum mechanical (QM/MM) approaches we show that the specific amino acid sequence of a short peptide genetically inserted between the cyt c553 holoprotein and the surface anchoring C-terminal His6-tag plays a crucial role in ensuring the optimal orientation and distance of the heme group with respect to the SLG surface. Consequently, efficient DET occurring between graphene and cyt c553 leads to a 20-fold enhancement of the cathodic photocurrent output compared to the previously reported devices of a similar type. The QM/MM modeling implies that a perpendicular or parallel orientation of the heme group with respect to the SLG surface is detrimental to DET, whereas the tilted orientation favors the cathodic photocurrent generation. Our work confirms the possibility of fine-tuning the electronic communication within complex bio-organic nanoarchitectures and interfaces due to optimization of the tilt angle of the heme group, its distance from the SLG surface and optimal HOMO/LUMO levels of the interacting redox centers.

A series of non-aggregated zinc phthalocyanine derivatives containing either bulky thiophenol or phenol substituents were synthesized as a novel donor component for bulk heterojunction (BHJ) solar cell applications. The molecular structure and photophysical properties of ZnPc derivatives were investigated by combined experimental and theoretical studies using density functional theory (DFT) and time-dependent DFT (TD-DFT) methods. In order to evaluate the physical properties of ZnPcs in the solvent environment, we applied the conductor-like polarizable continuum model (CPCM). Within this scope, light-harvesting efficiency (LHE), excited-state lifetime (τ), maximum absorption wavelengths (λmax), oscillator strength (f) and hyperpolarizability (β tensors) were calculated both in vacuum and chloroform (e = 4.9) medium. Furthermore, divergent types of global descriptors such as EHOMO, ELUMO, and bandgap (Egap) energies, ionization potential (I), electron affinity (A), hardness (η), and electrophilicity index (ω) were also calculated. Our computational findings revealed that the linker heteroatoms [sulfur for the ZnPc (1–2); oxygen for the ZnPc (3–4) including the substituent type (isopropyl for the ZnPc (2–4), and phenyl for the ZnPc (1–3] severely affected the photophysical properties of the dyes. In relation, theoretical results are in good accordance with our experimental observations. Finally, ZnPc derivatives were used as a donor component and PC61BM as an acceptor material in BHJ solar cells, displaying a maximum power conversion efficiency of 0.8%. Compared with ZnPcs 1–2, ZnPc 3–4 based cells showed an inferior photovoltaic performance. These results are promising and should encourage further studies on BHJ solar cells using near-infrared absorbing and non-aggregated ZnPcs.

In recent years, phthalocyanines (Pcs) have been widely used as photosensitizer in photodynamic therapy applications. Because of their strong absorptions in the near-infrared region (640-700 nm). The integration of phthalocyanine derivatives to a nanoparticle is expected to be efficient way to improve the activity of the photosensitizer on the targeted tissue. It is known that the integrated molecules not only show better accumulation on tumor tissue but also reduce toxicity in healthy tissues. In this study, the ZnPc molecule was synthesized and integrated to the TiO2 nanoparticle, to investigate the potential of PDT and its cytotoxicity. Additionally, ZnPc and ZnPc-TiO2 molecules were labeled with 131 I and it was aimed to put forth the nuclear imaging/therapy potentials of 131 I labeled ZnPc/ZnPc-TiO2 by determining in vitro uptakes in mouse mammary carcinoma (EMT6), human cervical adenocarcinoma (HeLa). In result of our study, it was observed that the radiolabeling yields of the synthesized ZnPc and ZnPc-TiO2 with 131 I were quite high. In vitro uptake studies shown that 131 I-ZnPc-TiO2 could be a potential agent for nuclear imaging/treatment of breast and cervical cancers. According to PDT results, ZnPc-TiO2 might have as to be a potential PDT agent in the treatment of cervical tumor. ZnPc and ZnPc-TiO2 might be used as theranostic agents.

Exhaust after treatment systems have become a necessity to eliminate pollutant emissions as required by standard. Nowadays, DOC and SCR are widely used after treatment technologies in diesel vehicles. In this experimental study carried on DOC and SCR systems, two different catalysts as Al 2 O 3 -TiO 2 /Fe 2 O 3 and Al 2 O 3 -Pt/Fe 2 O 3 were produced with impregnation method. The catalysts were characterized by Field Emission-Scanning Electron Microscope (FE-SEM), X-ray diffraction (XRD), X-ray fluorescence (XRF) and Brauner–Emmett–Teller (BET). Each catalyst was tested as DOC and SCR in real working state to see the effect of catalyst on pollutant emissions in diesel engine. Results showed that the use catalysts as DOC led to significant decrease in CO, HC, NO and smoke emissions. The exhaust temperature rose up to 50 °C after DOC. The use of catalysts in SCR system eliminated NO x emission by high rates. Furthermore; the use of catalysts in emission control systems led to an increase in specific fuel consumption and a decrease in excess air coefficient of engine.

Phthalocyanines (Pcs) are commonly used as Photosensors (PSs) in Photodynamic Therapy (PDT) applications due to their intense absorption in the far red-near IR spectral region with a high extinction coefficient and high ability for generating singlet oxygen. Pcs targetspecifically tumors, and do not show any considerable toxic effects under the absence of light. In particular, their chemical versatility has allowed the introducion a number of substituent at the periferal or axial positions which provide modulating photophysical properties, increases the solubility of these compounds in organic solvents. Nanoparticles increase the bioavailability, stability, and transport of PSs to target tissue. TiO2 nanoparticles are prefered in these applications because of their non toxic, low cost and high chemical stability properties. In our study, a Zinc Phthalocyanine (ZnPc) was used as a photosensor. The design of ZnPc integrated TiO2 nanoparticles is intended to make PSs a more effective PDT agent. With the aim to examine the nuclear imaging/treatment potentials of ZnPc and ZnPc-TiO2 in hepatocellular carcinoma (HepG2), colorectal adenocarcinoma (HT29) tumor and human healthy lung (WI38) cell lines in vitro study ZnPc and TiO2-ZnPc were also labeled with 131I. It is determined that 131I-ZnPc-TiO2 nanoparticle show a potential as an agent for the imaging/treatment of hepatocellular cancer by in vitro. The toxicity studies revealed that TiO2 nanoparticle decreases the toxicity of ZnPc. In vitro PDT results show that TiO2-ZnPc has a potential as a PDT agent in colon tumor treatment. Consequently, synthesized ZnPc and ZnPc-TiO2 could be promising candidates as theranostic agents.

The self-assembled supramolecular structures have recently attracted rising interest in view of their potential application in artificial photosynthesis, supramolecular electronics and many other scientific disciplines. In particular, self-assembled zinc chlorophyll nanowires appear to be highly promising candidates in the field of artificial photosynthesis and organic photovoltaics. In this work, the electrical conductivity properties of chlorosomal rod self-aggregates have been investigated by conductive atomic force microscopy (C-AFM). Two zinc chlorin derivatives bearing different length alkyl chains (ZnChl-C6 and ZnChl-C18) were prepared, and current–voltage characteristics of self-assembled zinc chlorin nanowires were investigated. The electrical conductivity and charge-carrier mobility of zinc chlorin nanowires were found to be 0.93 S/cm and 5.80 × 1 0 − 2 cm 2 / V s , respectively. It is worth noting that these self-assembled zinc chlorin nanowires revealed higher electrical conductivity and the mobility than those of previously published chlorophyll derivative supramolecular nanowires.

Imidazolium salts and derivatives have antitumor efficacy and toxic effects in different micro-organisms. In this study, an imidazolium bromide salt (NMI) was synthesized, and its antitumor potential was investigated by in vitro studies. Radiolabeling of synthesized NMI was carried out by iodogen method using 131 I radionuclide. The yield of radiolabeling was determined as 98.5 ± 0.1%. After that, cytotoxicity and intracellular uptake studies were evaluated in various cell lines. The cytotoxicity of NMI was determined as 35, 20, 10, and 1 μm for HEK-293, PC-3, CaCo-2, and MCF-7 cells, respectively. In addition, the intracellular uptake of 131 I-NMI was investigated in the cell lines, and the uptake was significantly found as 4 hr for MCF-7 and 6 hr for PC-3. In future studies, antitumor efficacy of 131 I-NMI on tumor-bearing animal model might be studied in light of these results.

A major bottleneck in the fabrication of efficient bio-organic nanoelectronic devices resides in the strong charge recombination that is present at the different interfaces forming the complex system. An efficient way to overcome this bottleneck is to add a self-assembled monolayer (SAM) of molecules between the biological material and the electrode that promotes an efficient direct electron transfer whilst minimising wasteful processes of charge recombination. In this work, the presence of a pyrene-nitrilotriacetic acid layer carrying different metal centers as SAM physisorbed on graphene is fully described by mean of electrochemical analysis, field emission scanning electron microscopy, photoelectrochemical characterisation and theoretical calculations. Our multidisciplinary study reveals that the metal center holds the key role for the efficient electron transfer at the interface. While Ni2+ is responsible for an electron transfer from SAM to graphene, Co2+ and Cu2+ force an opposite transfer, from graphene to SAM. Moreover, since Cu2+ inhibits the electron transfer due to a strong charge recombination, Co2+ seems the transition metal of choice for the efficient electron transfer., Comment: 28 pages, 7 figures

Cu2ZnSnS4 (CZTS) nanoparticles (NPs) were prepared by a simple hydrothermal method, and their cytotoxic, antiproliferative and proapoptotic activities on human non-small cell lung adenocarcinoma A549 cells were investigated for the first time, and the morphological and ultrastructural changes of these cells were monitored. The structural characterizations of the synthesized nanoparticles were made by using Field Emission-Scanning Electron Microscope (FE-SEM), X-Ray Powder Diffraction (XRD) and Raman techniques. Cytotoxicity and confocal microscopy studies revealed that the CZTS NPs effectively entered into the A549 cells in a dose-dependent not time-dependent manner over a period of 24 and 48 h. It was observed that the CZTS NPs had a negligible cytotoxic effect and considerable antiproliferative and proapoptotic activities. The low cytotoxicity of the CSTZ NPs and their potent anticancer activity against A549 cells highlight their potential to be used as anticancer agents. This study may pave the way for designing and constructing various morphologically diverse, nanotextured materials with desired functional attributes.

In this study, a novel polyethersulphone (PES) composite membrane incorporated with two different zinc phthalocyanines (ZnPc), tetra-iodo and octa(2,6-diphenylphenoxy), was fabricated through the phase inversion approach. Three different concentrations of zinc phthalocyanines (0.5, 1.0, and 2.0 wt.%) were blended into the PES membrane. The morphology and performance of the fabricated composite membranes were systematically studied by scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) mapping, atomic force microscopy (AFM), porosity, water contact angle, antifouling, and rejection measurements. Hydrophobicity of the pristine membrane decreased from 79.67° to 77.03° and from 79.67° to 67.57° after blending of 2.0 wt.% tetra-iodo ZnPc (TI-ZnPc) and octa(2,6-diphenylphenoxy) ZnPc (DP-ZnPc), respectively. Furthermore, the porosity and mean pore radius decreased due to the introducing of ZnPc. Porosity of the pristine membrane decreased from 60.60 % to 44.96 % and 42.21 % after blending of TI-ZnPc and DP-ZnPc, respectively. Mean pore size of the pristine membrane decreased from 22.70 nm to 9.11 nm and 17.93 nm after blending of TI-ZnPc and DP-ZnPc, respectively. BSA filtration mostly affected the flux of pristine membrane and caused it to decrease from 133.5 to 87.1 L/m2h (relative flux reduction (RFR) of 34.7 %). RFR decreased up to 19.2 % and 17.3 % for TI-ZnPc 2.0 wt% and DP-ZnPc 2.0 wt% composite membranes. Pristine PES membrane rejected 45.8 % BSA. However, TI-ZnPc 2.0 wt% and DP-ZnPc 2.0 wt% composite membranes supplied 91.0 % and 70.6 % BSA rejections, respectively. In comparison to pristine PES membrane, the total resistance (Rt) values of the composite membranes decreased. The pristine PES membrane showed the lowest flux recovery ratio (FRR, 71.89 %) against BSA, while all-composite membranes showed promising antifouling properties. FRR increased up to 97.44 % and 89.06 % for TI-ZnPc 2.0 wt% and DP-ZnPc 2.0 wt% composite membranes, respectively. The pristine PES membrane showed the lowest FRR against activated sludge, while all composite membranes showed promising antifouling properties. Moreover, ZnPc-embedded PES composite membranes were irradiated with appropriate wavelengths of light in the presence of oxygen to generate reactive oxygen species to clean fouled membranes’ surface. The results showed that photo-cleaning was very effective to recover membrane flux.

In this study, a novel polyethersulphone (PES) nanocomposite membrane incorporated with copper zinc tin sulfide (Cu2ZnSnS4) nanoparticles (CZTS NPs) was prepared through the phase inversion method. First, the samples containing different copper and zinc ratios in CZTS stoichiometry were prepared and characterized. The effect of copper and zinc ratio changes were examined on the photocatalytic properties of both NPs and nanocomposite membranes. The photocatalytic effect was tested and BR18 dye was degraded at 88.0% efficiency when exposed to visible light for 180 min in the presence of CZTS1.0 NPs catalyst. The results also exhibited that CZTS NPs blended membrane showed good self-cleaning performance. Second, we investigated the antioxidant, DNA cleavage, and biofilm inhibition activities of CZTS NPs. The antimicrobial activities of CZTS NPs were tested against seven microbial strains. The highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging and chelating activities were found as 81.80 ± 1.75% and 72.19 ± 4.63%, respectively. CZTS NPs exhibited double-strand DNA cleavage activity at 500 mg/L. They showed significant biofilm inhibition as 92.15 ± 5.67% against Staphylococcus aureus. CZTS NPs displayed moderate antimicrobial effects against tested microorganisms. Third, CZTS NPs were blended in polyethersulphone (PES) membrane and the morphology as well as performance of the fabricated nanocomposite membranes were systematically investigated by SEM-EDX, porosity, water contact angle, antifouling, and rejection measurements. The water flux of resulting nanocomposite membranes was markedly enhanced due to the introducing of CZTS NPs. Meanwhile, the nanocomposite membranes demonstrated remarkable antifouling properties (flux recovery ratio ∼94%) in contrast with the bare PES (flux recovery ratio ∼51%) when BSA was filtrated. The high retention of BSA (100%) as well as high permeation flux (73.8 ± 9.8 L/m2/h) of the CZTS2.00 wt% membrane demonstrated that the constructed nanocomposite membrane possessed the characteristics of a promising membrane for purification of proteins.

This study was performed to synthesize membranes of polyethersulfone (PES) blended with graphene oxide (GO) and PES blended with GO functionalized with photoactive semiconductor catalyst (TiO2 and ZnO). The antifouling and self-cleaning properties of composite membranes were also investigated. The GO was prepared from natural graphite powder by oxidation method at low temperature. TiO2 and ZnO nanopowders were synthesized by anhydrous sol–gel method. The surface of TiO2 and ZnO nanopowders was modified by a surfactant (myristic acid) to obtain a homogeneously dispersed mixture in a solvent, and then GO was functionalized by loading with these metal oxide nanopowders. The PES membranes blended with GO and functionalized GO into the casting solution were prepared via phase inversion method and tested for their antifouling as well as self-cleaning properties. The composite membranes were synthesized as 14%wt. of PES polymer with three different concentrations (0.5, 1.0, and 2.0%wt.) of GO, GO-TiO2, and GO-ZnO. The functionalization of membranes improved hydrophilicity property of membranes as compared to neat PES membrane. However, the lowest flux was obtained by functionalized membranes with GO-TiO2. The results showed that functionalized membranes demonstrated better self-cleaning property than neat PES membrane. Moreover, the flux recovery rate of functionalized membranes over five cycles was higher than that of neat membrane.

Porphyrin sensitizer (Por) containing 4-carboxybiphenyl and 2-thienyl and its metallated Zn(II) derivative (ZnPor) were synthesized and investigated. The porphyrin dyes were characterized by MALDI-MS, 1H NMR, UV–vis, fluorescence and cyclic voltammetry methods. It was found that using of biphenyl bridge between anchoring group and porphyrin core enhanced the conjugation length of the porphyrin macrocycle. The new porphyrin dyes were used as sensitizers in dye-sensitized solar cells (DSSCs). ZnPor-based dye sensitized solar cells yielded a short circuit photocurrent density of 3.98 mA cm−2, an open circuit voltage of 500 mV, and a fill factor of 0.67, corresponding to an overall conversion efficiency (η) of 1.33%.

The stability of the optical parameters of a ruthenium polypyridyl complex (Ru-PC K314) film under varying annealing temperatures between 278 K and 673 K was investigated. The ruthenium polypyridyl complex thin film was prepared on a quartz substrate by drop casting technique. The transmission of the film was recorded by using Ultraviolet/Visible/Near Infrared spectrophotometer and the optical band gap energy of the as-deposited film was determined around 2.20 eV. The optical parameters such as refractive index, extinction coefficient, and dielectric constant of the film were determined and the annealing effect on these parameters was investigated. The results show that Ru PC K314 film is quite stable up to 595 K, and the rate of the optical band gap energy change was found to be 5.23 × 10- 5 eV/K. Furthermore, the thermal analysis studies were carried out in the range 298-673 K. The Differential Thermal Analysis/Thermal Gravimmetry/Differantial Thermal Gravimmetry curves show that the decomposition is incomplete in the temperature range 298-673 K. Ru-PC K314 is thermally stable up to 387 K. The decomposition starts at 387 K with elimination of functional groups such as CO2, CO molecules and SO3H group was eliminated between 614 K and 666 K., State Planning Organization of Turkey (DPT2003K120390); Scientific and Technological Research Council of Turkey (TBAG-109T240)

ZnO nanopowder was synthesized via a hydrothermal route and characterized with several methods such as XRD, TG/DTA, FT-IR, FE-SEM, TEM and Electron Paramagnetic Resonance spectroscopy (EPR) in order to investigate the effect of growing time and Mn doping on the defects which occurred. The pure ZnO nanopowder was obtained in a hexagonal phase with (101) as the preferred orientation except for the one prepared for 36 h which is (002). The growing time does effect the orientation of the crystallite whereas the Mn-doping does not. The concentration of Mn2+ significantly increases the spin–spin interaction in the ZnO : Mn nanopowder. It was observed that there was a competition between intrinsic (Zn and O vacancies) and extrinsic (Mn2+ ion) structural defects but still the former defects are dominant in ZnO : Mn. The effect of growing time and concentration of Mn2+ on the activation energy of ZnO and the ZnO : Mn nanopowder are calculated by Kissinger–Akahira–Sunose (KAS) and Flynn–Wall–Ozawa (FWO) methods.

The fabrication of highly efficient bio-organic nanoelectronic devices is still a challenge due to the difficulty in interfacing the biomolecular component to the organic counterparts. One of the ways to overcome this bottleneck is to add a self-assembled monolayer (SAM) in between the electrode and the biological material. The addition of a pyrene–nitrilotriacetic acid layer to a graphene metal electrode enhances the charge transfer within the device. Our theoretical calculations and electrochemical results show that the formation of a pyrene–nitrilotriacetic acid SAM enforces a direct electron transfer from graphene to the SAM, while the addition of the Ni2+ cation and imidazole reverses the charge transfer direction, allowing an atomic control of the electron flow, which is essential for a true working device.

We report the fabrication of an oriented bioelectrode of photosystem I (PSI) on single-layer graphene (SLG). This bioelectrode demonstrates improved photocurrent generation, which can be directly attributed to the molecular conductive interface formed by cytochrome c553 (cyt c553) promoting the uniform orientation of PSI with its donor side towards the electrode. The conductive interface between PSI-cyt c553 and SLG is facilitated by a monolayer composed of ?-?-stacked pyrene functionalized with the Ni-NTA moiety, which binds the His6-tagged cyt c553. The surface uniformity of the PSI protein orientation in the electrode structure is evidenced by cross-sectional scanning electron microscopy and fluorescence microscopy, with the latter also proving the efficient electronic coupling between majority of the PSI complexes and graphene. With the uniform organization of the biological photoactive layer, photocurrents are generated at the open circuit potential, which can be further increased when a negative potential is applied. Indeed, at the highest applied negative potential (-0.3 V), over 5-fold increase in the cathodic photocurrent for the PSI complexes conjugated via cyt c553 to the SLG substrate is observed compared with that obtained for the randomly oriented structure where PSI is physisorbed on graphene. These results indicate the key role of a strictly defined orientation of photoactive proteins on electrodes for proper electron transfer and substantial improvement in photocurrent generation in the present or similar bioelectrode architectures. © 2018 The Royal Society of Chemistry.

It has become inevitable to design non-enzymatic biosensors to eliminate the drawbacks of enzymatic biosensors prepared using enzymes which are expensive and without long-term stability. For this purpose, a single layer graphene film was prepared by chemical vapor deposition method on Cu foil and transferred to the FTO glass slide. After that copper nanoparticles (CuNP) were decorated by the inert-gas condensation method based on DC magnetron sputtering on it. The prepared CuNP decorated graphene film was characterized and used as a non-enzymatic sensor platform for the detection of glucose. The sensor platform exhibited a fast response time of less than 4 s and the sensitivity of 430.52 μA mM−1 cm-2 with linear concentration range (0.01–1.0 mM) having detection limit 7.2 μM. Electrochemical investigations indicate that the sensor platform which is decorated CuNP graphene film possess an excellent performance toward glucose. Prepared biosensors platform could be used and applied in the field of new drug discovery, biomedical, clinical diagnosis and forensic science to miniaturize of detection instrument and reduce detection sample and period. © 2018 Elsevier B.V.

Novel octylthio-containing asymmetrically substituted Zn(II) phthalocyanine (Zn(II)Pc1) and a symmetric derivative (Zn(II)Pc2) have been prepared to investigate the biological potential and ability to photosensitize singlet oxygen for photodynamic therapy applications. In this study, the singlet oxygen generation potential and in vitro photodynamic activities of these compounds have been tested. Both ZnPcs reveal to be very efficient singlet oxygen generators and promising PSs for PDT applications. In vitro PDT activities of the compounds were evaluated in EMT-6 murine mammary carcinoma and HeLa human cervix carcinoma cell lines. Moreover, Zn(II)Pc1 displayed the phototoxic effects in the mammary cancer cell line (6.25 μm concentration at 30 J/cm(2) light dose and 12.5 μm concentration at 20 J/cm(2) light dose), while Zn(II)Pc2 did not show any phototoxic effects both in two cell lines. Zn(II)Pcs were radiolabeled with (131) I in high yields. Biodistribution studies revealed that the radiolabeled Zn(II)Pc1 showed significant uptake in l. intestine, pancreas, brain, and ovary, while Zn(II)Pc2 has significant uptake in ovary and pancreas in normal rats. Hence, these Pcs derivatives could be promising candidate for tumor nuclear imaging.

The zinc selenide (ZnSe) nanocrystal thin films have been prepared on glass substrates by chemical bath deposition at 80 degrees C. The ZnSe films have been annealed in an air atmosphere at 373, 473, 573, 673 and 773 K for 1 h. The crystallographic structure and size of the crystallites, dislocation density, number of crystallites per unit surface area and strain have been studied by X-ray diffraction on as-deposited and annealed films. The surface morphology of ZnSe coated thin films obtained at different annealing temperatures has been elucidated by AFM studies. The optical properties of the films have been investigated by recording the transmission spectra. It has been observed that the energy band gap decreases upon annealing temperature. The conductivity measurements have been carried out using four probe methods. It is observed that the conductivity and activation energy change upon annealing temperature.

In this study a new adsorbent, ionic liquid (1,8-naphthalene monoimide bearing imidazolium salt) coated carbon nanospheres, was synthesized for the first time and it was used for the solid phase extraction of copper and lead from various samples prior to determination by flame atomic absorption spectrometry. The ionic liquid, carbon nanospheres and ionic liquid coated carbon nanospheres were characterized by using Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, H-1 NMR and C-13 NMR, Brunauer, Emmett and Teller surface area and zeta potential measurements. Various parameters for method optimization such as pH, adsorption and elution contact times, eluent volume, type and concentration, centrifuge time, sample volume, adsorption capacity and possible interfering ion effects were tested. The optimum pH was 6. The preconcentration factor, detection limits, adsorption capacity and precision (as RSD%) of the method were found to be 300-fold, 0.30 mu g L-1, 60 mg g(-1) and 1.1% for copper and 300-fold, 1.76 mu g L-1; 50.3 mg g(-1) and 2.2%, for lead, respectively. The effect of contact time results showed that copper and lead were adsorbed and desorbed from the adsorbent without vortexing. The equilibrium between analyte and adsorbent is reached very quickly. The method was rather selective for matrix ions in high concentrations. The accuracy of the developed method was confirmed by analyzing certified reference materials (LGC6016 Estuarine Water, Reference Material 8704 Buffalo River Sediment, and BCR-482 Lichen) and by spiking sea water, wastewater, street dust and spice samples. (C) 2016 Elsevier B.V. All rights reserved.

The change in the crystal and electronic structure properties of wurtzite ZnO nanoparticles was studied according to Mn doping in the powder samples. The investigations were conducted by X-ray Absorption Fine Structure Spectroscopy (XAFS) technique for the samples prepared with different heating and doping processes. Electronic analysis was carried out by the collected data from the X-ray Absorption Near-Edge Structure Spectroscopy (XANES) measurements. Additional crystal structure properties were studied by Extended-XAFS (EXAFS) analysis. Longer heating periods for the undoped wurtzite ZnO samples were determined to own stable crystal geometries. However, for some doped samples, the distortions in the crystal were observed as a result of the low doping amounts of Mn which was treated as an impurity. Besides, the changes in oxygen locations were determined to create defects and distortions in the samples. (C) 2016 Chinese Materials Research Society. Production and hosting by Elsevier B.V.

Novel artificial zinc chlorin dyes comprising amine anchoring groups zinc aminochlorin (ZnChl-NH2), zinc monomethylaminochlorin (ZnChl-NHMe) and zinc dimethylaminochlorin (ZnChl-NMe2) are synthesized and their photovoltaic performances are evaluated in dye-sensitized solar cells. To the best of our knowledge, -NH2 functionalized Zn chlorin dyes are tested in dye-sensitized solar cells for the first time. Best efficiency is obtained with ZnChl-NHMe sensitizer with a 2.67 mA/cm(2) short circuit photocurrent density, 414 mV of open circuit voltage, 0.64 of filling factor, and 0.68 of overall light to power conversion efficiency. (C) 2015 Elsevier B.V. All rights reserved.

To design sensitizers for dye sensitized solar cells (DSSCs), a series of zinc chlorins with different substituents were synthesized. Novel zinc methyl 3-devinyl-3-hydroxymethyl-20-phenylacetylenylpyropheophorbide-a (ZnChl-1), zinc methyl 20-bromo-3-devinyl-3-hydroxymethylpyropheophorbide-a (ZnChl-2), zinc methyl 3-devinyl-3-hydroxymethyl-pyropheophorbide-a (ZnChl-3), zinc propyl 3-devinyl-3-hydroxymethyl-pyropheophorbide-a (ZnChl-4) were synthesized and their photovoltaic performances were evaluated in dye-sensitized solar cells. Photoelectrodes with a 7 μm thick nanoporous layer and a 5 μm thick light-scattering layer were used to fabricate dye sensitized solar cells. The best efficiency was obtained with ZnChl-2 sensitizer. ZnChl-2 gave a Jsc of 3.5 mA/cm2, Voc of 412 mV, FF of 0.56 and an overall conversion efficiency of 0.81 at full sun (1000 W m−2).

Fabrication and characterization of highly effcient organic light-emitting diode with surface modification of indium tin oxide anodes by using self-assembled monolayer technique have been studied. Four different self-assembled molecules, K-28 ruthenium complex, octadecylamine hydrochloride, octadecyltrichlorosilane and mercaptohexdecanoic acid are used to modify ITO surface to improve the interface properties. Space charge limited currents measurements have been used to evaluate carrier mobility under steady state current. The results show that the surface properties such as the stability of ITO anode layer have significant effects on charge injection in organic light-emitting diode devices., TUBITAK under grant No. TBAG-108T718